.nav_{
	height: 60px;
	background-color: #aaaaaa;
}
.bef_4 a{
	color: red;
}
.aft_4 a{
	color:black;
}
ul li a{
	text-decoration: none;
}
ul{
	margin-left: 20%;
}
ul li{
		list-style-type: none;
		float: left;
		text-align: center;
		display: block;
		height: 60px;
		width: 100px;
}
ul li:hover{
	text-decoration: underline;
	background-color: #eee;
}
